What Causes Post Nasal Drip?

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What is post-nasal drip? Post nasal drip is literally like a runny nose in the back of your throat. Just about everybody has had that yucky sensation of mucus running down the back of your throat, forcing you to either swallow it or cough it up. So attractive. It couldn't politely come out of your nostrils like a runny nose, right? Oh, no: This mucus goes the other way, from your nose into the back of your throat. Actually, it is normal for a certain amount of mucus to drain into the back of your throat on a regular basis. When we're not sick we don't even notice it. It's when another condition increases the amount of mucus that it becomes bothersome. Severe post-nasal drip usually leads to a sore throat and coughing. In some cases the tissue in the back of the throat, including the tonsils, can swell and it may feel like there is a lump in your throat.

Possible Complications of Post-Nasal Drip

You've heard the expression, "insult to injury," right? Post-nasal drip is a perfect example.

Ear Infections. Your throat and middle ear are connected by the Eustachian tube, which equalizes air pressure on either side of your eardrum. All that coughing and clearing your throat to try to get rid of the mucus can push some of it into this tube. What can happen then? You guessed it: an ear infection.

If you have ear pain (which may indicate an infection) during a bout with post-nasal drip, or if your "drip" lasts longer than a couple of weeks, contact your doctor. 

Sinus Infections. This is a case of double insult to injury: Sinus infections can both cause and be caused by post-nasal drip! The "caused by" part comes in when post-nasal drip prevents your sinuses from draining properly.

What Causes Post-Nasal Drip?

You may be sorry you asked. Why? Because the answer is, "Just about everything." Here are some of the many causes of post-nasal drip:

  • allergies to pollen, mold, dust, or dander
  • infections such as the common cold (for example, from CMV, RSV, adenovirus, and other viruses), influenza, and sinusitis 
  • swallowing disorders (may result in actual post-nasal drip or just cause the sensation of having it)
  • strep throat (post-nasal drip is an uncommon strep throat symptom, but it can occur)
  • pregnancy and other conditions that cause fluctuation of hormone levels
  • dehydration
  • eating spicy foods
  • eating too many dairy products, especially if you're not drinking enough water
  • low humidity
  • certain medications, including contraceptives and antihypertensives to control blood pressure
  • foreign objects stuck in the nose
  • overuse of pseudoephedrine nasal sprays (this can lead to condition called rebound congestion  or nasal spray addiction where nasal symptoms become much worse anytime the nasal spray is stopped)
  • anatomical abnormalities such as a deviated septum or enlarged turbinates
  • acid reflux (gastrointestinal reflux disease, or GERD)
  • weather changes

What Can I Do About Post Nasal Drip?

Fortunately there are a number of things you can do to make your post-nasal drip more tolerable. Here are some tips:

  • drink a lot of water to keep your mucus thin (thin mucus is easily swallowed and less bothersome)
  • use a cool mist humidifier at night while you sleep
  • see a doctor to treat underlying conditions such as allergies, chronic sinusitis, or infections
  • avoid caffiene
  • don't use diuretics (medications that get rid of extra fluid through increased urination)
  • some over-the-counter medications such as guaifenesin may help to thin mucus (consult your doctor or pharmacist before using new medications)
  • try using a net pot
  • try a saline nasal spray
  • avoid using decongestants that contain a steroid (pseudoephedrine, oxymetazoline) for longer than three days at a time
  • sore throat symptoms may be eased with over-the-counter medications such as acetaminophen or cough lozenges
  • if you suffer from acid reflux don't sleep flat at night (make sure your head is elevated)

What Else Should I Know?

  • Post-nasal drip is a worsening of what's actually a normal condition: You always have mucus draining down your throat, but you don't usually notice it.
  • Post-nasal drip is rarely an emergency, but get medical help if you're choking, drooling. or unable to swallow.
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Article Sources
  • "Post-nasal drip." American Academy of Otolaryngology - Head and Neck Surgery (2015).  
  • “Nasal discharge.” U.S National Library of Medicine-MedlinePlus (2013).